Horton

Re: Poorly thought out code in vacuum

Robert Haas <robertmhaas@gmail.com>

View thread
From: Robert Haas <robertmhaas@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Simon Riggs <simon@2ndquadrant.com>, pgsql-hackers@postgresql.org
Date: 2012-01-06T17:45:55Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Make VACUUM avoid waiting for a cleanup lock, where possible.

On Fri, Jan 6, 2012 at 12:34 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> On Fri, Jan 6, 2012 at 12:24 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> So at this point I've got serious doubts as to the quality of testing of
>>> that whole patch, not just this part.
>
>> I tested the case where we skip a block during the first pass, but I
>> admit that I punted on testing the case where we skip a block during
>> the second pass, because I couldn't think of a good way to exercise
>> it.  Any suggestions?
>
> Hack ConditionalLockBufferForCleanup to have a 50% probability of
> failure regardless of anything else, for instance via
>
>        static int ctr = 0;
>
>        if ((++ctr) % 2)
>                return false;

Oh, that's brilliant.  OK, I'll go try that.

Note to self: Try to remember to take that hack back out before committing.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company